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United States Patent | 5,255,442 |
Schierbeek ,   et al. | October 26, 1993 |
An electronic compass is described for use in vehicles. The compass employs a magnetoresistive sensor for sensing the earth magnetic field and the sensor is operated in alternate set/reset bias modes. The compass is provided with deviation compensation by a closed loop system including measurement of the sensor output signals and an offset current strap for nullifying the vehicle deviation field.
Inventors: | Schierbeek; Kenneth L. (Zeeland, MI); Schofield; Kenneth (Holland, MI) |
Assignee: | Donnelly Corporation (Holland, MI) |
Appl. No.: | 811578 |
Filed: | December 20, 1991 |
Current U.S. Class: | 33/361; 33/333; 33/356; 324/252 |
Intern'l Class: | G01C 017/28; G01R 033/06 |
Field of Search: | 33/361,333,340,355 R,356,357 324/252 |
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